(19)

(11)

EP 0 958 622 A1

(12)

(43) Date of publication: 24.11.1999 Bulletin 1999/47 (21) Application number: 97920818.0 (22) Date of filing: 02.05.1997

(51) International Patent Classification (IPC):  H01L 27/ 32( . ) H01L 51/ 52( . ) H01L 51/ 50( . ) (86) International application number: PCT/GB1997/001208 (87) International publication number: WO 1997/042666 (13.11.1997 Gazette 1997/49)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 03.05.1996 GB 19960009282 (60) Divisional application: 06075364.7 / 1684368 (60) Divisional application: 06075367.0 / 1672721 (60) Divisional application: 06075382.9 / 1672722 (71) Applicant: Cambridge Display Technology Limited Cambridge, CB1 2JB (GB)	(72) Inventor: PICHLER, Karl Cambridge CB4 3EJ (GB) (74) Representative: Driver, Virginia Rozanne, et al  Page White & Farrer 54 Doughty Street London WC1N 2LS London WC1N 2LS (GB)